From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 13977 invoked by alias); 30 Jun 2013 13:59:10 -0000 Mailing-List: contact ecos-bugs-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: ecos-bugs-owner@sourceware.org Received: (qmail 13957 invoked by uid 89); 30 Jun 2013 13:59:09 -0000 X-Spam-SWARE-Status: No, score=-2.8 required=5.0 tests=AWL,BAYES_00,KHOP_RCVD_UNTRUST,KHOP_THREADED,RCVD_IN_DNSWL_LOW autolearn=ham version=3.3.1 Received: from hagrid.ecoscentric.com (HELO mail.ecoscentric.com) (212.13.207.197) by sourceware.org (qpsmtpd/0.84/v0.84-167-ge50287c) with ESMTP; Sun, 30 Jun 2013 13:59:08 +0000 Received: from localhost (hagrid.ecoscentric.com [127.0.0.1]) by mail.ecoscentric.com (Postfix) with ESMTP id 597A04680011 for ; Sun, 30 Jun 2013 14:59:05 +0100 (BST) Received: from mail.ecoscentric.com ([127.0.0.1]) by localhost (hagrid.ecoscentric.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id h7FsnwwVVc+p; Sun, 30 Jun 2013 14:59:01 +0100 (BST) From: bugzilla-daemon@bugs.ecos.sourceware.org To: ecos-bugs@ecos.sourceware.org Subject: [Bug 1001764] Enhancement of MMC/SD over SPI driver Date: Sun, 30 Jun 2013 13:59:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: eCos X-Bugzilla-Component: Disk X-Bugzilla-Keywords: X-Bugzilla-Severity: enhancement X-Bugzilla-Who: mjones@linear.com X-Bugzilla-Status: NEEDINFO X-Bugzilla-Priority: low X-Bugzilla-Assigned-To: unassigned@bugs.ecos.sourceware.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Bugzilla-URL: http://bugs.ecos.sourceware.org/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-SW-Source: 2013/txt/msg00468.txt.bz2 Please do not reply to this email, use the link below. http://bugs.ecos.sourceware.org/show_bug.cgi?id=1001764 --- Comment #22 from Mike Jones --- I have had more bench time on the MMC, so I have more information about its operation under heavy use. First, my setup is atypical. I have a cable on J5 of the Kinetis tower board that connects to another board 30cm away. This board has its own power supply off line. Therefore, because there is a ground connection in J5, there is a ground loop. Furthermore, I am using the I2C lines in the J5 connector. I have seen four problems: 1) Can't mount Samsung microSD 2) Can't mount any microSD 3) IO failure after three hours of intense operation (logging MB to card) 4) Can't get DMA to work reliably I have some new information. I was debugging the TWR-DACADC-LTC and noticed problem 2. When I removed the ground clips from my scope, problem 2 went away. This leads me to the conclusion that problems 2 and 3 are related to grounding problems. I can't prove grounding is causing 3 until I have a single board version of my solution. Problems 1 and 4 still seem to be problems that only affect me. I work around them by not using DMA and not using the Samsung card. I am certain that problem 1 is not related to grounding. I have tested for that. I am reasonable certain problem 4 is not related to grounding, I am pretty sure I have seen the problem with my cable removed. -- You are receiving this mail because: You are on the CC list for the bug.